I don't know whether it's Black Hat or Grey Hat,
but tiered link building has been working from the start until now. I started tiered link building with tools like Senuke, Magic Submitter, Sick Submitter, and now GSA SER and SEO AutoPilot or RankerX.
I mostly use GSA SER as it has a one-time fee, but I still purchase SEO AutoPilot or RankerX from time to time, especially when I build new websites.
The most important key is the ratio of anchor text: brandable anchor texts to main focus anchor texts.
Afterward, try to index them with a blast of tier 2 links or just use an indexer. Make sure to use a good verified link list and high-quality content (nowadays content management is super easy with AI).